The Dallas Cowboys owner has “slowed down, if not impeded” Goodell’s negotiations with the NFL for a new contract extension, ESPN’s Adam Schefter and Chris Mortensen reported Sunday.

It was reported in late August that Goodell was nearing a five-year extension that would keep him as league commissioner until 2024. That deal still isn’t done yet, though, and Jones apparently is a big reason why: The Cowboys owner has “interjected himself into the process of the NFL’s six-man compensation committee, becoming the unofficial seventh member,” according to Schefter and Mortensen.

In fact, one person familiar with the negotiations told ESPN.com that Goodell’s extension would be complete if it wasn’t for Jones. Sources also told Schefter and Mortensen that Jones is being “singled out” by owners and league executives as the reason why Goodell didn’t have a new deal before the start of the 2017 season.

Goodell, of course, has had his battles with league owners before, as New England Patriots owner Robert Kraft took the commish to task for suspending Tom Brady in Deflategate. But while Kraft and the Patriots eventually relented on Brady’s punishment, it appears Jones is ready to do battle with Goodell.

“The increasingly edgy relationship between Jones and Goodell has sharpened to the point where Goodell’s long-term future could be in question,” Schefter and Mortensen reported, citing sources.

Jones’ hard stance could just be bluster, but the fact remains that he’s one of NFL’s most powerful owners who has serious pull in league matters. As long as Goodell doesn’t have an extension in place, this is a situation worth monitoring.